Arc lamp



(No Model.)

W. L. SILVEY! ARC LAMP.

Patented May 28, 1889.

Inc/enter:

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UNITED STATES PATENT OEEIcE.

\VIIJIIIAM Ii. SILVEY, OF CINCINNATI, OHIO.

ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 403,964, dated May 28, 1889. Application filed November 12, 1887. Serial No. 254,959. (No model.)

To all whom, it may concern:

Be it known that I, IVILLIAM Ii. SILVEY, a citizen of the United States, residing at Oincinnati,in the county of Hamilton and State of Ohio, have inventedanew and useful Electric-Arc Lamp, of which the following is a the arc may not be disturbed in its position by any severe or undue amount of jarring, as on locomotives, &c., and at the same time the lamp may be placed in any position whatsoever without affecting its regulating mechanism or move the carbon points out of position, and, fifth, to provide alamp not affected by temperature and one not using any fluid or liquid dash-pots to rectify inherent de- To attain these objects, I employ the mechanism shown in the accompanying drawings, this being the most simple form to embody the essential features. However, different forms may be used, the moving mechanism being the only essential features.

Similar letters refer to similar parts.

Figure 1 a perspective view of the complete machine, all parts being in proper place. Fig. 2 is a top view of the lower half of Fig. 1 below the dot-ted line x :c; and Fig. is a central cross-sectionof the solenoid-magnet D, showing its internal arrangements.

The lamp-frame consists, essentially, of a column, A, which is preferably round, cast onto a base-plate, A, to which all the mechanism is attached. The upright column is finished to a regular diameter, and on it the sleeves 13 B are made to move. The upper sleeve, 13, has cast on one side the tail-pieced, through which the screw C passes. The front part has the overhanging arm (Z cast onto it, in the outer end of which there is a hole drilled, through which the short rod g passes for the support of the top-carbon holder at and top carbon, N.

The bottom sleeve, B, has cast on the back the tail-piece d, which is drilled and tapped like the upper one. Through this the lower end of the screw C passes. The front part of B has an overhanging arm cast onto it, the outer end supporting the solenoidmagnet D, the two being separated by an insulatingsleeve, Z). This solenoid-magnet is constructed as follows: The upper head, D and the center tube are non-magnetic material, as brass, &c, while the bottom head or anvil is iron. This iron head serves a double purposeone for confining the wire on the spool, the other to serve as a stationary armature or heel-piece for the movable iron core I). The action of this magnet is as follows: A current of electricity circulating in the helix 1) will magnetize the movable iron core D, which is immediately attracted by the anvil-block D to which it firmly adheres. This iron anvilblock serves the purpose of compensating for unequal current and to maintain the negative carbon n in one place, no matter in what position the lamp may be arranged. The lower end of the negative iron rod D' is turned to a stem, d, around which a spiral spring, 6, is coiled. This spring serves to raise the iron rod off the anvil-block when no current of electricity is flowing, at which time the attraction of magnetism ceases. The screw-rod O, which moves the carbons together, has two sizes of thread-a top thread, which occupies two-thirds of the length of the rod, and a bottom thread occupying one-third of the rodone beingrighthand and the other left-hand,

the pitch being so pro mrtioned that one end will move its carbon twice as fast as the other. I prefer to make the top screw eight threads to the inch and right-h and, while the bottom screw is sixteen threads to the inch and left-hand. On the lower end of this double screw rod I fasten a ratchet wheel, c.

By moving this wheel in one direction the.

carbons will approach each other, and in the other direction they will recede, owing to the action of the screw. Just above the ratchetwheel, but pivoted on the screw-rod O, is the armature-bar 10, one end of which serves as an armature for the clectro magnets E, while the other end serves as a carrier for the pawl 1 the spring on serving to keep the pawl at all times against the ratchet-wheel. If a current of electricity is made to flow through the IOO coils of the electro-magnets E, the armaturebar is attracted toward them at one end, the other end moving in an opposite direction. The pawl engages in the teeth of the ratchetwheel, turns the wheel and screw to which it is attached, imparting a simultaneous movement to the sleeves B B, and the carbons are made to approach each other. As soon as the electric circuit is broken the magnets lose their power and the fiat conical spring S pushes the armature w back till it rests against the stop-nuts r, the other end returns, and the ratchet takes a new hold. Every time this operation is repeated the current is made and broken at the point of contact between the insulated screw f and the springs. The regulating-n ut r is used to impart more or I less tension to the spring which serves to de termine the amount of current necessary to put the armature-bar w in motion. This spring also determines the length of arc between the carbons.

The electro-magnets E being in derived circuit, it is evident that the longer the distance between the carbon points the greater will be the resistance of the arc circuit and more current will be diverted through the shunt or derived circuit; consequently the magnets E will have more or less power according to the length of the arc.

The operation of the lamp is as follows: The current enters at the binding-post P,

passes to the column A, thence to the arm b,

rod g, carbon-holder a, to the top carbon, N. The negative current enters at the insulated binding-post P, thence by the insulated cable I to the coils of the solenoid D, from which it escapes to the spool D thence to the iron rod D, lower-carbon holder a, and negative carbon n. The derived circuit which moves the mechanism of the lamp enters at the negative binding-post P, passes thence to the fine-wire coils E along the circuit shown by dotted line Z, thence along short circuit to the insulated contactrscrew f, thence to contact-spring s and armature-bar w, from which it escapes to the frame-work of the lamp and binding-post P. In working,- the currententers at bindingpost P, from which it escapes to the several circuits already described. In the operation it is preferable to use a. shunt-wound dynamo, in order that the feed mechanism will close the carbon circuit or main circuit. As soon as the two carbons come in contact, the electro-magnet D draws the movable iron core D down against the iron bottom, against which it adheres, and the arc is formed between the carbon points. As soon as the distance becomes sufficient that the electro-magnets in the derived circuit have power to move their armature, thereby revolving the ratchetwheel, the carbons begin to approach each other. The motions of the mechanism in the feeding devices are repeated as often as it is necessary for the lamp to feed to compensate for the carbon as it burns away.

It is a well-known fact that the power of a magnet increases as the square of the distance; hence the motion of the armature-bar in a forward direction as soon as it has advanced far enough causes the spring S to draw away from the contact-screw f and break the circuit. The magnets E at once lose their power and the reacting spring S throws the armature back in its original position, at which time the derived circuit is again closed andthe operation is again repeated. At each operation the pawl moves the ratchet-wheel forward, and thereby forces the carbons to approach each other. This is continued at intervals until the carbons are entirely consumed.

Having fully described my invention, what I claim as new, and wish to secure by Letters Patent, is-

In a focusing arc lamp in which two carbon points are fed toward each other simultaneously, the combination of a differential screw with a ratchet-wheel capable of being turned in one direction only by the operation of a single electro-magnet whose coils are in a derived circuit around the arc, the armature of the electro-magnetpivoted on the difierential screw and having a pawl attached to one end for turning the ratchet-wheel, the other end having a spring-mounted circuit-breaker attached to it for the purpose of controlling the actions of the electro,.- nagnets, a single electric circuit performing the entire operation of feeding the positive carbon point downward and the negative carbonupward, as specified.

\VILLIAM L. SI LYEY.

\Vitnesses:

EDWARD KEISER, WILLIAM MITTENDORF. 

